Optical coupler having first and second terminal boards and first and second conversion elements

1. An optical coupler comprising: a first terminal board and a second terminal board; a first conversion element for converting an electrical signal into an optical signal mounted on a surface of a first element mounting section of the first terminal board; a second conversion element for converting an optical signal into an electrical signal mounted on a surface of a second element mounting section of the second terminal board; and a light reflective curved surface formed so as to cover the first conversion element and the second conversion element, wherein the surfaces of the first element mounting section and the second element mounting section have the same orientation, wherein an optical signal emitted from the first conversion element is reflected on the light reflective curved surface, to optically couple the first conversion element and the second conversion element, wherein the second conversion element has a plurality of light receiving cells that are electrically connected in series, arrayed in parallel with one another, and longer in a longitudinal direction than in a width direction, and wherein the first conversion element is arranged inside an area sandwiched between two contact lines that are set so as to be in contact with an outline of the second conversion element, and are in parallel with a length direction of the light receiving cells, and wherein the first conversion element is disposed in the length direction of the light receiving cells with respect to the second conversion element.

2. An optical coupler comprising: a first terminal board and a second terminal board; a first conversion element for converting an electrical signal into an optical signal mounted on a surface of a first element mounting section of the first terminal board; a second conversion element for converting an optical signal into an electrical signal mounted on a surface of a second element mounting section of the second terminal board; and a light reflective curved surface formed so as to cover the first conversion element and the second conversion element, wherein the surfaces of the first element mounting section and the second element mounting section have the same orientation, wherein an optical signal emitted from the first conversion element is reflected on the light reflective curved surface, to optically couple the first conversion element and the second conversion element, wherein the second conversion element has a plurality of light receiving cells that are electrically connected in series, arrayed in parallel with one another, and longer in a longitudinal direction than in a width direction, wherein the first conversion element is arranged inside an area sandwiched between two contact lines that are set so as to be in contact with an outline of the second conversion element, and are in parallel with a length direction of the light receiving cells, and wherein among the light receiving cells arrayed in parallel with one another, the light receiving cell located at the midsection has a narrower width and the light receiving cell located at the end has a wider width.

3. A MOS driver comprising: an optical coupler comprising: a first terminal board and a second terminal board; a first conversion element for converting an electrical signal into an optical signal mounted on a surface of a first element mounting section of the first terminal board; a second conversion element for converting an optical signal into an electrical signal mounted on a surfaces of a second element mounting section of the second terminal board; and a light reflective curved surface formed so as to cover the first conversion element and the second conversion element, wherein the surfaces of the first element mounting section and the second element mounting section have the same orientation, wherein an optical signal emitted from the first conversion element is reflected on the light reflective curved surface, to optically couple the first conversion element and the second conversion element, wherein the second conversion element has a plurality of light receiving cells that are electrically connected in series, arrayed in parallel with one another, and longer in a longitudinal direction than in a width direction, wherein the first conversion element is arranged inside an area sandwiched between two contact lines that are set to be in contact with an outline of the second conversion element, and are in parallel with a length direction of the light receiving cells, wherein the first conversion element is disposed in the length direction of the light receiving cells with respect to the second conversion element, and wherein a control circuit for driving a MOSFET is connected in parallel with the second conversion element.

4. A semiconductor relay comprising: an optical coupler comprising: a first terminal board and a second terminal board; a first conversion element for converting an electrical signal into an optical signal mounted on a surface of a first element mounting section of the first terminal board; a second conversion element for converting an optical signal into an electrical signal mounted on a surfaces of a second element mounting section of the second terminal board; and a light reflective curved surface is formed so as to cover the first conversion element and the second conversion element, wherein the surfaces of the first element mounting section and the second element mounting section have the same orientation, wherein an optical signal emitted from the first conversion element is reflected on the light reflective curved surface, to optically couple the first conversion element and the second conversion element, wherein the second conversion element has a plurality of light receiving cells that are electrically connected in series, arrayed in parallel with one another, and longer in a longitudinal direction than in a width direction, wherein the first conversion element is arranged inside an area sandwiched between two contact lines that are set so as to be in contact with an outline of the second conversion element, and are in parallel with a length direction of the light receiving cells, wherein the first conversion element is disposed in the length direction of the light receiving cells with respect to the second conversion element, wherein a control circuit for driving a MOSFET is connected in parallel with the second conversion element, and wherein MOSFETs are respectively connected to both ends of the connection circuit.